The clock has two separate lead off arbors. One conventional, that turns once each hour
and a second that turns once per minute. Therefor, this was meant to drive two separate
dials. The movement is normally rewound electrically through it's motor; mediated by a
complex electro-mechanical system, but can also be wound manually. The one minute
remontoire, in addition to supplying a constant source of power to the escapement, also
triggers a lever that energizes a solenoid to drive slaves. The system is reversible,
where an electrical impulse can be sent to the solenoid to trigger the remontoire once per
minute to let the mechanism act as a slave. It is not known to me why this would be
desirable. This type of system uses a reversing DC current (polarized) which was common in
Continental Europe to drive slaves. In contrast, England and the USA used a non-reversing
current. For another example of a mechanism using a polarized system see the Collin-Wagner master clock in the skeleton
section.

For more information on remontoire click here and a
video of this style of remontoire here.